Hippocrates was a greek physician born around -0460. He is considered to be “the father of medicine” because of his contributions to the systematic study of illness and medicine. The Hippocratic oath that physicians take, swearing to the ethical practice of medicine, is named after him. Before Hippocrates, superstition ruled medical beliefs and popular thinking was that illness was caused by possession, evil spirits and negative influence from the gods. Hippocrates believed that symptoms could diagnose illness, that each illness had a logical cause and could be treated. He also promoted the idea of treating the body as a whole and natural healing that depended on rest, fresh air and a good diet.